Non-volatile data storage devices, such as embedded memory devices (e.g., embedded MultiMedia Card (eMMC) devices) and removable memory devices (e.g., removable universal serial bus (USB) flash memory devices and other removable storage cards), have allowed for increased portability of data and software applications. Users of non-volatile data storage devices increasingly rely on the non-volatile storage devices to store and provide rapid access to a large amount of data. Additionally, non-volatile data storage devices may be configured to be coupled to another device, such as a host device, or may be used as storage components, such as solid state drives (SSDs), accessible to multiple servers at a data center.
Advances in memory device technology have resulted in memory devices that have a three dimensional (3D) configuration. A 3D memory device may include memory cells that are vertically stacked and positioned in different layers (e.g., different levels) of multiple vertically stacked layers. A group of memory cells that is vertically stacked may be coupled to a conductive channel. During manufacturing of the 3D memory device, a hole may be created through the multiple vertically stacked layers to enable formation of the conductive channel. However, as a number of layers that the hole extends through increases, controlling formation of the hole becomes difficult. For example, a shape of the hole may not be a cylindrical shape through all of the multiple layers; rather, the hole may have a tapered shape through one or more of the multiple layers. To illustrate, a cross-section of the hole through the multiple layers may have a conical shape or a funnel shape. When the hole does not have a consistent shape (e.g., a consistent diameter) through all of the multiple layers, physical dimensions of one or more memory cells may be affected which may result in reduced performance or failure of the one or more memory cells. Further, a channel formed in the hole that does not have a consistent shape may lead to variations in charge retention of memory cells coupled to the channel and may prohibit the memory cells from storing multiple bits per cell. Additionally, if the hole is formed through too many layers, the hole can become unstable and may collapse. Accordingly, a number of memory cells that may be vertically stacked, and thus a size and/or a storage density of the 3D memory device, may be limited based on the number of layers through which the hole may be formed.